Acute renal failure of obstetric origin is common among North Indian patients and comprised 72 (22.1%) of 325 patients undergoing dialysis over an 11-year period. Of these, 46 gravidas had developed renal failure following abortion, and 29 cases were due to complications of late pregnancy. The most striking feature of this study was a high incidence of irreversible renal lesions of bilateral diffuse cortical necrosis in early (18.6%) as well as late pregnancy (37.8%). Overall incidence of diffuse cortical necrosis was 25%. In the remainder, acute tubular necrosis was seen in 52 (72.2%), patchy cortical necrosis in 1 (1.4%), and tubular necrosis along with glomerular involvement in 1 patient (1.4%). Pathogenetic factors which contributed to the development of renal failure, either singly or in combination, were loss of blood failure, either singly or in combination, were loss of blood (79.1%), septicemia (31.9%), hypotension due th hemorrhagic and septicemic shock (51.4%), eclamptic toxemia (11.1%), and disseminated intravascular coagulation in 12.5% patients. Infrequent occurrence of disseminated intravascular coagulation in the septic anc eclamptic patients who developed diffuse cortical necrosis was an interesting finding, as was the fact that coagulopathy was more frequently observed in acute tubular necrosis. Late referral, frequent sepsis, and high incidence of bilateral diffuse cortical necrosis contributed significantly to a high mortality (55.3%).